The present application relates to a display apparatus and an electronic device, aid more particularly to a display apparatus wherein a plurality of light emitting elements such as organic electroluminescence elements are arrayed on a substrate and an electronic device which incorporates the display apparatus.
An organic electroluminescence light emitting element (organic EL element) which makes use of electroluminescence (EL) of an organic material attracts attention as a light emitting element which is superior in high speed responsibility and can emit light of high luminance by low voltage dc driving. The organic EL element includes an organic layer including a light emitting layer sandwiched between two electrodes such that emitted light is extracted through one of the electrodes. A display apparatus called organic EL display apparatus in which such an organic EL element as just described is used includes a plurality of organic EL elements arrayed on a substrate. Meanwhile, in an organic EL display apparatus of the active matrix driving type, a driving element is provided for each of pixels on a substrate, and organic EL elements are formed and arrayed on a flattening insulating film which covers such driving elements.
As one of configurations for allowing such an organic EL display apparatus as described above to achieve color display, a configuration is available wherein a light emitting material is formed in a pattern on a light emitting layer of each pixel. Also various other configurations are available including a configuration wherein a color filter and a color conversion layer are combined with a white light emitting element and another configuration wherein a common light emitting layer which emits white light is used and only a predetermined wavelength is taken out by multiple interference.
It is examined to apply such an organic EL display apparatus as described above not only to a large-sized display apparatus such as a monitor but also to such a small-sized display apparatus as represented by a viewer. In this instance, in order to differentiate the organic EL display apparatus from existing liquid crystal display apparatus from a point of view of the display performance, it is necessary to raise the performance of the organic EL display apparatus as high as possible.
Incidentally, a plurality of organic EL elements formed and arrayed on a flattening insulating film as described above are isolated from each other in the following manner by a rib. In particular, lower electrodes are provided in rows and columns and individually formed in a pattern in pixels such that they are individually connected to driving elements, and a rib is provided in a state wherein it covers peripheral edges of the lower electrodes. An organic layer including a light emitting element is formed and stacked on the lower electrodes which are exposed through openings of the rib, and an upper electrode is formed and stacked on the organic layer. It is significant that, in the state described above, the lower electrodes and the upper electrode are isolated from each other by the rib and the organic layers.
It has been proposed to form the rib in such a configuration that a corner of each opening is formed in an arcuate or polygonal shape in accordance with an arcuate shape of a corner portion of an organic layer, that is, an organic EL light emitting thin film, formed as a mask by vapor deposition through a metal mask. According to the configuration, short-circuiting between the lower electrode and the upper electrodes caused by displacement in pattern of the organic layer can be prevented. See, for example, Japanese Patent Laid-Open No. 2001-196171. Also another configuration is known and disclosed in Japanese Patent Laid-Open No. 2005-101009 wherein an edge portion at an end portion of an opening has some curvature and aside wall of the opening has an inclination angle.